Least possible (7)
(Other definitions for minimum that I've seen before include "Nadir" , "Least possible quantity" , "Lowest value" , "Lowest point" , "Least recorded value" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">least possible</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for minimal that I've seen before include "Token" , "Very little" , "barely worth considering" , "Least possible; negligible" , "Of the least possible size" .)